GnRHstimuleringstester

GnRH stimuleringstester, also known as Gonadotropin-Releasing Hormone stimulation tests, are diagnostic procedures used to assess the function of the hypothalamic-pituitary-gonadal axis. This axis plays a crucial role in regulating reproductive hormones and development. The test involves administering synthetic Gonadotropin-Releasing Hormone (GnRH) and then measuring the levels of specific hormones in the blood over a period of time.

The primary hormones monitored are Luteinizing Hormone (LH) and Follicle-Stimulating Hormone (FSH). These gonadotropins are released by the anterior pituitary gland in response to GnRH stimulation. The pattern and magnitude of LH and FSH release provide insights into the integrity of the pituitary gland's response to GnRH.

GnRH stimulation tests are typically employed in cases of suspected hypogonadism, delayed puberty, or disorders of sexual development in both males and females. For instance, in individuals experiencing delayed puberty, the test can help differentiate between primary hypogonadism (problem with the gonads) and secondary hypogonadism (problem with the pituitary or hypothalamus). A blunted or absent response in LH and FSH secretion suggests a pituitary or hypothalamic issue, while a robust response might indicate primary gonadal failure.

The procedure usually involves an initial blood draw to establish baseline hormone levels, followed by the intravenous or intramuscular administration of synthetic GnRH. Subsequent blood samples are collected at predetermined intervals, often every 15 to 30 minutes for up to two hours, to track the hormonal response. Interpretation of the results requires careful consideration of the patient's age, sex, and clinical presentation, alongside established reference ranges.